Electric weft detector for looms



Nov. 22, 1949 H. A. WHITIN 2,488,951

ELECTRIC WEFT DETECTOR FOR LOOMS Filed Dec. 30, 1948 I 3 Sheets-Sheet 1 FIG.I

INVENTOR HERBERT A. WHITIN ATTORNEY Nov. 22, 1949 H. A. WHITIN 2,483,951

ELECTRIC W FT DETECTOR FOR LOOMS Filed'Dec. 30, 1948 3 Sheets-Sheet 2 INVENTOR HERBERT A.WH|TIN 61ml IOO ATTORNEY Nov. 22, 1949 H. A. WHITIN 2,488,951

ELECTRIC WEFT DETECTOR FOR LOOMS Filed Dec. 50, 1948 z Sheets-Sheet z INVENTOR HERBERT A. WHITIN ATTORNEY.

Patented Nov. 22, 1949 UNITED STATES PATENT OFFICE ELECTRIC WEFT DETECTOR FOR LOOMS Application December 30, 1948, Serial No. 68,152

Claims.

This invention relates to electromechanical weft detectors for looms and it is the general object of th invention to provide controls for such a detector which will prevent a false indication when the weft detector is removed from the path of the incoming bobbin during a weft replenishing operation of the 100m.

In weft replenishing looms of the multicolor type it is customary to mount the weft detector at the magazine end of the loom and move the detector forwardly at the time of bobbin transfer to avoid damage thereto by the outgoing and incoming bobbins. When the detector finger is of the side slip type it is likely to swing on its pivot incident to forward movement and thus close its contact to give a false indication. Unless provision is made to prevent this false indication from being completed a second unnecessary transfer Will occur.

One type of multicolor Weft replenishing loom to which the invention is applicable employs a setting lever normally at rest but lifted preparatory to a transfer not only to raise the latch of the transferrer arm but also rock the magazine should such rocking be necessary. When the magazine is rocked it must be maintained in its rocked position until the transferrer arm has returned to its normal raised position and this is effected by keeping the lever in raised position during the period that the transferrer arm is away from its normal position.

It is an important object of the present invention to provide an electric weft detecting system employing an electromechanical feeler of the side slip type having a switch which is closed by the detector when it indicates weft exhaustion and having a second switch which is controlled by the aforesaid lever. The second switch is normally closed when the lever is down, but when it is raised its switch is open for a period beginning at least as early as transfer starts and continuing at least until the transferrer arm has returned to its raised position. The second switch is therefore open throughout the entire period of activity of the transferrer arm and ample time is provided for return of the side slipping detector finger to its normal position before the second switch is closed.

In another type of multicolor weft replenishing loom a stationary magazine having plural stacks of reserve bobbins is associated with a normally raised transferrer arm which descends incident to replenishment as the lay advances and then returns to its raised position as the lay recedes. In a modified form of the invention the second switch is mounted so as to be kept closed by the transferrer arm when it is in its normal raised position so that the detector circuit can be completed, but opens as the transferrer arm starts down to prevent a false closure of the circuit as the detector is moved forwardly out of the path of the incoming bobbin.

With these and other objects in view which will appear as the description proceeds, the invention resides in the combination and arrangement of parts hereinafter described and set forth.

In the accompanying drawings, wherein two forms of the invention are set forth,

Fig. 1 is a side elevation of part of one type of weft replenishing loom having the preferred form of the invention applied thereto, the lay, shuttle box and shuttle being in cross section.

Fig. 2 is an enlarged plan view looking in the direction of arrow 2, Fig. 1, showing the manner in which the detector indicates weft exhaustion.

Fig. 3 is a view similar to Fig. 2 but indicating the manner in which the detector can give a false indication when moved forwardly on a replenishing beat of the loom.

Fig. a is a vertical section on line i4, Fig. 2,

Fig. 5 is a diagram representing the electric circuit employed with the invention,

Fig. 6 is a side elevation of a multicolor stationary magazine and .weft detector having the modified form of the invention applied thereto,

Fig. 7 is an enlarged plan view looking in the direction of arrow 7, Fig. 6, and

Fig. 8 is a diagram of the detector circuit used with the modified form of the invention.

Referring particularly to Fig. 1 wherein the preferred form of the invention is shown, a loom frame I!) supports a reserve bobbin magazine M which in the present instance is provided with front and back stacks Ii and I2 of reserve bobbins. The magazine is mounted for rocking movement about a fixed pivot 13 on a foot or support l4 secured to the loom frame. A link 15 extends rearwardly from the magazine to a bell crank lever it from which depends a rod 11 the lower end of which is fitted with a hook I8.

An actuator lever 20 pivoted on a fixed stud 21 carries a roll 22 which is located in the groove 23 of a cam 24 secured to the bottom shaft 25 on the loom. The forward end of lever 29 has mounted thereon a movable dog 26 which rises and falls regularly during loom operation in a two-pick cycle due to rotation of the cam 24 by the bottom shaft.

The position of hook I8 is controlled by a selector lever 30 moving about a fixed pivot 3| and attached to a connector 32 which leads to the shifting shuttle box mechanism at the opposite side of the loom. A second normally stationary setting lever 33 has an operating stud 34 at the rear end thereof for cooperation with the hook E8. The forward part of the setting lever 33 is provided with a shelf or lug 35 for cooperation with the dog 26. The latter is under control of two fingerstii and 3'; which are normally out of controlling or indicating position and permit the dog to rise'and fall without engagement with the lifting lug 35. Ifhese fingers are on a carriage 38 connected by rod 35 to lever to so that whenever the latter rocks the fingers change their registry with dog 26.

A solenoid S normally deenergized is effective when energized to move one or the other fingers 35 or 37 to indicating position, in which position the finger will direct the dog into engagement with the lug 35 upon its next upward movement. This effects rocking a lever 33 in a clockwise direction as viewed in Fig. 1 to depress the setting stud 34, and if the hook is is under the stud the magazine will be rocked in a clockwise direction, Fig. l, to place the lowest bobbin in the rear stack K2 in transfer position. If the hook it is in its other position out of register with stud 3d the magazine remains in its normal position shown in Fig. l with the lowest bobbin of the front stack l i in transfer position.

When lever 33 rocks as already described it lifts a link 49 connected to its forward end the effect of which is to rock a latch positioning lever ii clockwise about its fixed pivot 42, thereby raising a rod 3 which lifts a transfer latch 3 into the path of a hunter 45 on the lay. The latch is connected in usual manner to a transferrer arm 66 which upon downward movement as the bunter 45, moving forwardly or to the left, Fig. 1, engages latch 4 :presses a bobbin into shuttle 4? on the lay 48.

Since the magazine may be in its abnormal or rocked position due to engagement of hook i8 by stud 34, it is necessary to hold the magazine in its rocked position until the transferrer arm 46 returns to its normal up'position. The transfer reaches this latter position during the first part of the rearward motion of the lay, after which the lever 33 can rock in a counterclockwise direction to permit return of the magazine to its normal position and also lower the rodil. The lever 33 is therefore seen to be in its indicating or setting position throughout the period during which the transferrer arm is moving, and is held in that position by the periodically rocking lever 2% due to the control exerted over the latter by cam 2d.

The transferrer arm 66 rocks about a stationary stud B which in the present instance has secured thereto a fixed stand 5! to which a support 52 is secured by a bolt 53. Support 52, see Fig. 4, has a hub 54 in which is slidably mounted a rod 55. The rod 55 supports the detector which is designated generally herein at D. See prior Patent No. 2,304,181.

Except as noted hereinafter the matter thus far described may be of common construction similar to that set forth in prior Patents Nos. 2,128,914 and 2,162,290.

The weft detector comprises a casting 68 in 7 has an adjustable operating screw settherein for cooperation with a finger 67 secured to and moving with the transferrer arm 46.

A thin preferably sheet metal plate 10 is secured to the underside of the casing 69 by two bolts H and has secured to the rear end thereof an upstanding stud "52 on which is pivotally mounted a lever 73. This lever is acted upon by a spring i l surrounding the stud 12 in such manner as to hold the lever yieldingly in the normal position shown in full lines in Fig. 2. Secured to lever 13 is a tube 15 in which is slidably mounted a detector finger 76. The stud i2 is surrounded by a drum l7 and one end of the spring M is connected to the arm 73 and the other end is connected to the drum. A set screw i8 holds the angular setting of the drum with respect to the stud and therefore determines the force which the spring exerts on the lever 73 tending to hold it in normal position.

The lever 13 has a small depending finger 80 which normally engages the plunger SI of an electric switch 82. The switch is of such construction that when the plunger 'is pushed inwardly by the finger 86 due to action of spring M the switch will be open, but when the finger 8 0 moves away from the plunger due'to angular motion of lever 73 the switch closes.

It will be apparent from Fig. 2 and 3 that the greater part of the detector finger is at one side of the pivotal stud 12. When a bobbin transfer" occurs arm 6? on the transferrer armmoves screw 58 and casting to forwardly in order that the detector finger it may be moved out of the path of the outgoing and incoming bobbins B l and B2, respectively, see Figs. 2 and 3. Because of the manner of pivoting the detector finger the latter due to its momentum tends to turn in a clockwise direction as viewed in Figs. 2 and 3 around the stud 12, or from the full line to the dotted line position shown in Fig, 3. This swinging motion of the detector f nger and lever 13 and 89, respectively. A compression or expan-' sion spring 92; tends normally to move bottom 89 away from the upper contact 88," but is normally prevented from doing so by engagement of a rod or pin 9! on contact 89 with a stop 92 mounted in fixed position, as on the stud 2|. When lever 33 is down in its normal position it moves the rod 9| against the stop 92, threby lifting the bottom contact 89 against the upper contact 88 and under these conditions the following electric detector circuit will be completed when the detector swings to the right to close switch 82, see Fig. 5: Transformer T, solenoid S, wire 95, contact 95 within switch 82, contact 97, forced agai'nst contact 9d by expansion spring 58, wireSS, contacts 83 and 89, and wire Hi8 back to the transformer. This circuit will be closed when a depleted shuttle is at the magazine end of the loom and causes swinging of the detector to indicating position, and lever 33 is in'its normal down position.

At a later time in loom operation the lever 20 will receive a periodic oscillation from the cam 24 and lift the forward or left end of lever 33 as viewed in Fig. 1, thereby setting the loom for a weft replenishing operation as already described, and also lifting the pin 9I away from the stop 92, whereupon the spring 90 moves contact 89 down away from contact 88. The circuit previously described is therefore open at switch 81 and when the detector moves forwardly incident to operation of the transferrer arm 46 and lever I3 swings to the dotted line position of Fig. 3, the circuit will not be completed because of the fact that lever 33 will still be in raised setting position at the time of transfer and will remain raised until the transferrer arm returns to its normal up position. The rocking of the weft detector finger incident to forward motion of the detector rod therefore does not close the detector circuit and the solenoid S will not be energized a second time as would otherwise be the case if the circuit were not open at the contacts 8889.

The second or modified form of the invention is shown as applied to the usual form of multicolor bobbin changing weft replenishing loom. Referring particularly to Figs. 6-8, the magazine MI is shown as having four stacks of reserve bobbins IIO, III, H2 and H3. The magazine has the usual provision for delivering bobbins from these stacks one at a time so that they move to a transfer position designated at Il l. arm II5 is mounted on the usual stud H6 and has a latch IIl for engagement with a bunter H8 on the lay H5 The latch is normally in the down position shown in Fig. 6, but when a replenishing operation is called the latch will be raised into the path of the hunter and as the lay advances the transferrer arm will descend to insert the bobbin in transfer position into a shuttle I on the lay.

The mechanism for calling the weft replenishing operation, shown more particularly in Fig. '7, employs an electromechanical side slip weft detector I2I which when having a side slipping movement incident to indication of weft exhaustion closes a normally open switch I22. A solenoid I23 when energized rocks a shaft I24 to move a controller or chopper pin I25 connected thereto into the path of an actuator or chopper lever I25. The normal down motion of the lever I25 is thus interrupted to initiate a replenishing operation of the magazine and lifting of the latch III as already mentioned.

Multicolor weft replenishing mechanisms of the type shown more particularly in Figs. 6 and 7 are of well-known construction and a further detailed description of them is not thought necessary.

Secured to the magazine frame is a second switch I32 having a plunger I3I positioned for engagement with the transferrer arm H5 when the latter is in its normal raised position. Switch I is so constructed that when the plunger I3I thereof is raised due to the fact that the transferrer arm is in its normal idle raised position the switch will be closed, but when the transferrer arm starts down to effect transfer the plunger I3I moves downwardly and effects opening of the switch I30.

Fig. 8 shows diagrammatically the circuit which can be used with the modified form of the invention. This circuit shows a transformer T supplying alternating current having a wire I35 connected to one pole of switch I30 and having a second wire I3i5 connected to one side of switch I22. The other side of the latter is connected The transferrer to one side of the solenoid I23 the other side of which is connected by wire I3I to the other pole of switch I30. Weft detection ordinarily takes place while the transferrer arm is raised and when the detector indicates weft exhaustion the circuit shown in Fig. 8 will be closed to energize the solenoid due to simultaneous closure of the switches I22 and I30. When a later replenishing operation occurs and the transferrer arm descends switch I30 will be open, which will open the detector circuit, and keep it open during practically the entire time that the transferrer arm is in motion, that is, away from its normal position. If, as the detector is moved forwardly by the transferrer arm as already described more particularly in connection with the preferred form of the invention, a false indication should be given with resultant closure of switch I22, the circuit of Fig. 8 will still remain open due to the fact that switch I30 has opened as a result of downward movement of the transferrer arm. Switch I30 will not close until the transferrer arm reaches its normal raised position, but by this time the weft detector will have recovered any tendency which it has to swing and give a false indication.

From the foregoing it will be seen that the electric detector system set forth herein employs a circuit having two switches one of which is normally open but closed by the detector when the latter indicates weft exhaustion, whether correctly or falsely, and the other of which is normally closed but is open during a transferring operation of the loom, thereby preventing a false indication by the detector which might occur incident to operation of the transferrer arm. In the preferred form of the invention the lever 33 must remain in its raised or setting position long enough to permit the transferrer arm to return to its raised position before the magazine rocks back to its normal condition can occur. The normally closed switch is thus held open and the detector finger has ample time to return to its normal position. In the modified form of the invention the transferrer arm itself effects opening of the second switch, but it is apparent that this control of the switch could also be used with the transferrer arm shown in Fig. 1.

Having thus described the invention it will be seen that changes and modifications of the foregoing specific disclosure may be made without departing from the spirit and scope of the invention.

What is claimed as new is:

1. In an electric weft detecting system for a weft replenishing loom, a normally open detector electric switch, a normally closed control electric switch, replenishment controlling electric circuit means closed only when said switches are both closed, a weft detector tending to close the detector switch falsely on replenishing beats of the loom, and means effecting opening of the control switch on weft replenishing beats of the loom.

2. In an electric weft detecting system for a 55 weft replenishing loom, bobbin transfer mechanormally closed controlelectric switch which opens during said period to prevent closure of thecircuit means should the detector give a false indication incident to movement thereof by the transfer mechanism.

3. In an electric weft detecting system for a weft replenishing loom, an electric weft detector at the weft replenishing side of the loom, transfer mechanism operating during a givenperiod of the cycle ofa weft replenishing beat of the loom and effective during said period to move the weft detector from the normal position thereof, said detector when thus moved by the transfer mechanism tending to give a false indication of weft exhaustion, and electric circuit means closed only when both switches are closed and effective when closed tocause a replenishing operation of the loom, said circuit means including a normally open detector electric switch and a control electric switch normally closed except during said period, said detector switch being closed by the detector to close the circuit means if the detector correctly indicates weft exhaustion on a non-replenishing beat of the loom prior to said period and saidcontrol switch due to being open during said period preventing closure of said circuit means should the weft detector give a false in dication during said period.

4. In an electric weft detecting system for a weft replenishing loom' having a weft detector and a member forming part of the'replenishing mechanism of the loom which moves away from the normal position thereof incident to a weft replenishing operation of the loom, an electromagnetic device which is energized preparatory to a replenishing operation, electric circuit means including the device and two electric switches which when both are closed close the circuit means, one of said switches being normally open but closed by the detector'whenever the latter indicates weft exhaustion and the other switch being normally closed by said member when the latter is in normal position but opening when said member is away from the normal position thereof, opening of said other switch incident tov a replenishing operation preventing closure of said circuit means by said one switch if the detector should falsely indicate weft exhaustion during a replenishing operation.

5. In an electric weft detecting system. for a weft replenishing loom, bobbin transfer mechanism having a given period of operation during weft replenishing beats of theloom, a setting lever which moves from the normal position thereof to the setting position thereof prior to said period to set the transfer mechanism for operation and remains in setting position throughoutsaid period, an electric weft detector moved from. the normal position thereof by the transfer mechanism when the latter has said given period of operation and tending due tomovement thereof by the transfer mechanism to give a false indication'of weft exhaustion, a normally open switch closed when the weft detector indicates weft exhaustion, a control switch maintained closed by said setting lever when the latter is in the normal position thereof but open when said lever is in the setting position thereof, and replenishing controlling'electric circuit means including said switches and being closedwh'en the detector closes the normally open switch while.

the control switch is closed but being open. if the detector during said; period gives a false indication and closes the normally open switch due to e: the factthat said control switch. is open. during said period.

6'. In an electric weft detecting system for a.

weft replenishing loom, bobbin transfer mechanism normally at rest, a setting lever normally at rest, an electric weft detector moved by the transfer mechanism on a replenishing beat: of the-loom, a detector electric switch normally. open but closed by the detector when the-latter indicates weft exhaustion, a normally closed control electric switch controlled by the setting lever and closed only when the latter is in normal position, means responsive to closure of the detector switch when the control switch is closed effective.

to move said lever from the normal to the setting position thereof, said transfer mechanism thereupon having a-period of operation occurring within the-tirne'that the control lever is in the setting position thereof, said detectortending to give a false-indication with resultant closure of the detector switch incident to movement thereof by the transfer mechanism, and replenishment controllingelectric circuit means including said switches closed-when the detector switch is closed by the detector on a non-replenishing beat of the loom and open during said period due to opening of the control switch regardless of whether the detector gives a false indication and closes said detector switch.

7. In an electric weft detecting system for a weft replenishing loom, bobbin transfer mechanism having a given period of operation during a weft replenishing beat of the loom, a weft detector which has a movement derived from the transfer mechanism during said period and tends due to such movement to give a false indication of weft exhaustion, a normally open detector electric switch closed whenever the detector gives an indication of weft exhaustion, a control switch normally closed by the transfer mechanism except during said period, and replenishing controlling electric circuit means closed only when said detector and control switches are both closed.

8. In an electric weft detecting system for a weft replenishing loom, a bobbin transferrer arm normally at rest but operating during a given period of. a weft replenishing cycle of the loom; an electric weft detector which is given a m'ove ment by the transferrer arm during said period and tending'due to said movement to give a false indication of weft exhaustion, a normally open detector switch closed whenever the detector indicates weft exhaustion, a control switch closed by the transferrer arm when the latter is at rest but being open when said transferrer arm operates during said period, and replenishment controlling electric circuit means including said switches closed when the detector switch is closed during closure of the control switch but open if a false indication by the detector closes the detector' switch during said period.

9; In an electric weft detecting system for" a weft replenishing loom, a side slipping weft de tector' mounted for back and forth movement relatively to the lay, an electric detector contact closed by the detector whenever the latter has a side slipping movement regardless of the back and forth position of the detector, transfer mechanism moving the detector forwardly on replenishing beats of the loom and causing the detector to have a side slipping movement, an electric control contact normally closed but being open during movement of the detector by the transfer mechanism, and replenishment controlling electric circuit means including said contacts and closed only when both contacts are closed, said circuit means being incapable of closure if the detector when moved by the transfer mechanism closes the detector contact due to the fact that the control contact will then be open.

10. In an electric weft detecting system for a weft replenishing loom, transfer mechanism moving during a weft replenishing operation of the loom, a side slipping weft detector which is given a movement by the transfer mechanism during a replenishing operation, an electric detector contact normally open but closed by the detector incident to said movement thereof by the transfer mechanism, an electric control con- 10 tact normally closed but being open during movement of the transfer mechanism, and replenishment controlling electric circuit means closed only when said contacts are both closed.

HERBERT A. WHITIN.

REFERENCES CITED The following references are of record in the file of this patent: 

